The new episode "Patagonia: The Ends of the Earth" travels to the far tip of South America to visit a seemingly magical realm that appears to be frozen in time. Patagonia is a land of extremes, from the dizzying heights of the Andes mountain range to coastal fjords. In these extreme conditions, any life follows one of two strategies: specializing in a single habitat and living there exclusively, or somehow evolving to become tough enough to endure multiple conditions. Helena Bonham Carter narrates.